Post questions and info about safe and unsafe materials that can be or should not be used to construct a launcher. Also post things about different universal accessories for your cannon (breech loader, muzzle break, etc.)

I bought some small plastic pipe made for use in sinks for an airsoft barrel and since it is not pvc I had to glue it with epoxy. I tried to glue it so that the pipe would go through an end cap but the epoxy won't hold it together . I sanded the pipe and and tried it again bot it still couldnt stick. I looked at the label and the pipe wasnt made out of the type of plastic that epoxy doesnt stick to. I can't figure it out.

Do you know what plastic it's made of? Polypropylene and especially HDPE (polyethylene) is almost impossible to glue, but I've heard good things about using polyurethane glue on these. And cleaning is important in any case.

I've had alot of problems with JB weld... Make sure you sand the surfaces and mix the epoxy well. You might be able to use some duct tape and just force it in. Then screw bolts in the side. It holds pretty well. It depends the type of your connection though.